How do I change Artist's tag?

Sorry, English is not my 1st language so my grammar might be weird, and I'm not sure if I'm allowed to write it here though.

But I made a mistake, and I don't know how to fix it. I searched solutions myself but I couldn't find any.

I just added artist, roadrunner to upload female gunner image.

But I found out there are other images tagged with roadrunner(but I assume they didn't make artist tag.). And it's not the images from same artist.

Other images by different artist, but I assume they have same name. (1) , (2)

I tried to change artist's alias or information, but I couldn't find out how to do it.

The best,

I think those were tagged with "roadrunner" as a general tag. It only shows up as an artist tag now because you made it one. See how they are both tagged with another artist tag as well. If the roadrunner tag is going to continue referring to that artist, it should be removed from those two posts. But it might be worth qualifying the artist's tag, like "roadrunner (bmd21118)" (from their pixiv username).